How To Fix DDLS366 - Parent view & contains union; extends are not allowed

SAP Error Message - Details

• Message type: E = Error

• Message class: DDLS - For DDL source handling

• Message number: 366

• Message text: Parent view & contains union; extends are not allowed

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

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Smart SAP Assistant

• What is the cause and solution for SAP error message DDLS366 - Parent view & contains union; extends are not allowed ?

  The SAP error message DDLS366 indicates that there is an issue with the definition of a view in the Data Dictionary (DDIC) where the parent view contains a UNION operation. In SAP, when you create a view based on another view that uses a UNION, you cannot extend that view with additional fields or further operations. This is because UNION operations in SQL combine the results of two or more SELECT statements, and extending such a view can lead to ambiguity and complexity in the data structure.
  Cause:
  The error occurs when:
  
  You are trying to create a new view that extends a parent view which already contains a UNION operation.
  The system does not allow extending views that are based on UNIONs due to the complexity and potential for conflicting data structures.
  
  Solution:
  To resolve this error, you can consider the following approaches:
  
  
  Avoid Extending the Parent View: Instead of trying to extend the parent view, create a new view that directly selects from the underlying tables or views that the parent view is based on. This way, you can avoid the complications introduced by the UNION.
  
  
  Modify the Parent View: If possible, consider modifying the parent view to eliminate the UNION operation. This may involve restructuring the underlying data model or combining the logic in a different way.
  
  
  Create Separate Views: If you need to work with the data from the parent view and also need additional fields, consider creating separate views that handle each requirement independently.
  
  
  Use Database Views: If the logic allows, consider using database views instead of DDIC views, as they may provide more flexibility in terms of SQL operations.
  
  
  Related Information:
  
  Documentation: Check the SAP Help Portal or the ABAP documentation for more details on view definitions and restrictions.
  SAP Notes: Look for any relevant SAP Notes that might address this specific error or provide additional context or workarounds.
  Community Forums: Engage with the SAP Community or forums where other developers may have encountered and resolved similar issues.
  
  By following these steps, you should be able to resolve the DDLS366 error and successfully create the necessary views in your SAP environment.